So it's been about a month since I lost my beautiful Sammy dog. And whilst I am still feeling her loss I'm wondering about my cat too.

Lately it seems like he can't stop eating. He's always had a healthy appetite but he is almsot constantly craving food now. Could this be a sign he is grieving for Sammy too? He was a kitten and I already had Sammy when I got him, so as far as he knows Sammy has always been there. If he is feeling down is there anything I can do to help him?
(Besides getting a new pet)

I don't know about cats but dogs certainly do grieve - I've seen it.

They will look for the lost dog for maybe weeks afterwards. It's the pack instinct. One of their own hasn't come back.

They do eventually move on though. That too is nature and the instinct to go on and survive.

Sorry you lost Sammy. It really is the downside of animal ownership.

Animals grieve. Not all of them but some definitely do. We had a lab that missed his brother dreadfully when he died - it probably took 3 or 4 months before he stopped trying to drag us over to any dark coloured dog of roughly the right size, beside himself with excitement until he realised it wasn't him.

If practical - and it isn't always - it's recommended that other pets in a family are allowed to see, sniff and even groom their deceased pack / family member and some animals do seem to understand the animal is no more and don't keep looking.

I've not had a cat that has grieved for any other family member but if your cat is ravenous, tbh, it's more likely to be the time of year. Even a neutered male will sense spring in the air and with that and moulting their winter coat and growing their spring one, it is surprising how much their appetites increase for a few weeks. I'd say I've upped the food I need to put down for my cats by about a quarter to a third over the past 10 days. But it happens around this time every year.

However, it could be that your cat needs worming or, depending on its age, there could be some other physical "thing" going on. If he's otherwise healthy though, not losing weight and is under the age of, say, 10, I'd say the increased appetite is just due to the time of year.